One billion is a really big number and one billion people means more than one in every eight people living on Earth right now. But still there are several tech giants who have more than one billion active users. There are several aspects of achieving and managing this huge user base; it requires top notch idea, management, investment, marketing and great products. In this post we shall not focus in all these aspects, we shall only discuss about the system design of a product that can serve a really really huge user base.

We shall begin with a very small scale, from deploying the first server for handful of users. Then we shall gradually walk through different challenges as the number of users grow and discuss about ways to solve them. You should keep in mind that the nature and magnitude of the problems discussed here can differ greatly with the type and purpose of the system.

If you have studied a bit about RDBMS (Relational Database Management System), you may have heard of ACID properties. If you already know what the ACID properties are and what they do, then “Congratulations”, you do not need to read this post, there is nothing new I shall offer to you. But if you have heard about ACID properties but did not look deep to find out what they are, or the term “ACID properties” is new to you, then hang on a little, let’s discuss about this a little.